The feasibility of using the reactions $\{e+N({\epsilon }_i,J_i)\to e^{\prime }+,N({\epsilon }_f,J_f\left)\right\}\left\{\searrow N\right({\epsilon }_{\mathrm{ff}},J_{\mathrm{ff}})+\gamma \}$ to investigate low-lying states of heavy nuclei is discussed. By detecting the decay photon, the problem of poor energy resolution for high-energy electrons can be circumvented. The formalism for the $e^{\prime }-\gamma$ coincidence cross section is given. The Coulomb distortion of the electron wave functions, which is important for heavy nuclei, is taken into account. Results for the $e^{\prime }-\gamma$ coincidence cross section and the $\gamma$-detection cross section for several nuclei are given. The $e-\gamma$ coincidence cross section appears to be feasible when superconducting accelerators became operational. The $\gamma$-detection cross section offers a method for investigating low-lying states with present-day accelerators.

• Received 8 May 1970

DOI:https://doi.org/10.1103/PhysRevC.2.441